Trihalomethanes in Drinking Water of Greater Québec Region (Canada): Occurrence, Variations and Modelling

The levels of trihalomethanes (THMs) – the main species of by-product from water chlorination – were monitored in thedistribution systems of the five major drinking water utilitiesof the greater area of Québec City in order to investigate andmodel their occurrence on a spatial and seasonal basis. Data forTHMs and other water quality and operational parametersassociated with their formation were generated through a 16 monthsampling program involving several sites representing variablewater residence times, from the plant to the system extremity.The results demonstrate that the differences in measured THMlevels between the five utilities are mainly due to the variablequality of raw waters, the type of water treatment process beingused and the type and levels of applied disinfectant. Dependingon the utility, average THM levels were from 1.3 to 2.5 timeshigher in the system extremities than in the water leaving thetreatment plant. Also, average levels of THMs measured in summerat the distribution system extremities were, depending on theutility, from 2.5 to 5 times higher than the average levelsmeasured in winter. The seasonal differences were found to besignificantly greater than those observed by others in waterutilities in the United States and Europe and are explained inlarge part by the considerable changes, over the year, in thequality and temperature of surface waters in Southern Québec. Forthe five utilities under study, multivariate regression modelswere developed in order to predict spatial and seasonalvariations of THMs. Both residual chlorine demand and temperaturewere found to be better, statistically, as predictors for THMoccurrence. The usefulness of the developed models for routineand long term water quality management, as well as for assessmentof human exposure to THMs, are also discussed.     

Biodiversity and industry ecosystem management

The term biodiversity describes the array of interacting, genetically distinct populations and species in a region, the communities they comprise, and the variety of ecosystems of which they are functioning parts. Ecosystem health, a closely related concept, is described in terms of a process identifying biological indicators, end points, and values. The decline of populations or species, an accelerating trend worldwide, can lead to simplification of ecosystem processes, thus threatening the stability and sustainability of ecosystem services directly relevant to human welfare in the chain of economic and ecological relationships. The challenge of addressing issues of such enormous scope and complexity has highlighted the limitations of ecology-as-science. Additionally, biosphere-scale conflicts seem to lie beyond the scope of conventional economics, leading to differences of opinion about the commodity value of biodiversity and of the services that intact ecosystems provide. In the face of these uncertainties, many scientists and economists have adopted principles that clearly assign burdens of proof to those who would promote the loss of biodiversity and that also establish near-trump (preeminent) status for ecological integrity. Electric utility facilities and operations impact biodiversity whenever construction, operation, or maintenance of generation, delivery, and support facilities alters landscapes and habitats and thereby impacts species. Although industry is accustomed to dealing with broad environmental concerns (such as global warming or acid rain), the biodiversity issue invokes hemisphere-wide, regional, local, and site-specific concerns all at the same time. Industry can proactively address these issues of scope and scale in two main ways: first, by aligning strategically with the broad research agenda put forth by informed scientists and institutions; and second, by supporting focused management processes whose results will contribute incrementally to the broader agenda of rebuilding or maintaining biodiversity.     

CHARGES FOR URBAN RUNOFF: ISSUES IN IMPLEMENTATION1

ABSTRACT: Maryland officials have identified stormwater utilities as a potential method of financing programs to control nutrients in urban stormwater runoff that are proposed in Maryland's Chesapeake Bay Nutrient Reduction Plan. This paper reviews a number of issues related to the equity, efficiency and acceptability of user charge schemes. Overall, charges are found to be preferable to property taxes from both equity and efficiency perspectives. In addition, evidence suggests that elected officials will support creation of utilities. Obstacles to the implementation of utilities are identified.     

Comparative analysis of air pollution emissions by electric utilities: Public policy implications

One of the objectives of US environmental regulations was to reduce industrial air pollution emissions, especially from the electric utility industry, the major industrial air polluter. In this study, a comparative analysis of air pollution emissions from fossil-fuel-burning electric utility plants is conducted. The analysis focuses on a 12-yr period from 1975 to 1987 for three air pollutants: particulates, surfur dioxide, and nitrogen oxides. The results indicate that particulate emissions have been significantly reduced but that sulfur dioxide and nitrogen oxides are still major problems for a number of plants. Furthermore, the disparity in the performance by plants indicates that by using current technology, the industry as a whole could greatly reduce these emissions. These results have policy implication for future environmental legislation.     

MUNICIPAL RESPONSES TO VOLATILE ORGANIC COMPOUNDS IN WISCONSIN GROUND WATER1

ABSTRACT: Contamination of ground water supplies with volatile organic compounds is a new and significant problem. Municipalities and their community water systems are often the first to discover ground water contamination because of the monitoring programs they are required to carry out. When contamination exceeds standards, some action is required. The responses of Wisconsin municipalities to volatile organic compounds that exceed standards in their ground water sources is described. Actions to protect human health are prompt, but the survey results indicate plumes of contaminated ground water are usually not treated. They may continue to migrate and contaminate other private and public wells.     

OWNERSHIP AND WATER SYSTEM OPERATION1

ABSTRACT: Two types of organizational systems provide most of the water service in the United States. The investor-owned firm operates on a profit basis generally subject to state commission regulation. The government-owned firm is generally confronted by local control. The comparative efficiency of private versus government firm provision of water services is essentially an empirical issue. Unit costs and other operating statistics are examined for water firms of each ownership form. The analysis shows that private firms tend to have higher operation costs than do government firms, possibly attributable to wage-salary differentials. The analysis also indicates that capital investment in large government firms may result in diseconomies. The analysis creates serious doubt as to whether efficient provision of water services can be better facilitated by large mergers of either ownership form.     

COST BEHAVIOR AND WATER SYSTEMS1

ABSTRACT: Several factors theoretically affect the cost behavior of water systems. These factors include scale, consumer density, and per capita usage. This analysis examines the several possible influences on the unit costs of water service. The statistical analyses indicate that among the factors of scale, per capita use, and consumer density, only the first two factors are important influences on water system costs. Water consumers appear to benefit from being served by large systems and being located in service areas characterized by relatively high per capita consumption. There is little statistical evidence indicating that more dense areas can be provided water service at lower costs than less dense areas.     

The influence of the operational environment on the efficiency of water utilities

Adjusting for the operational environment in studies of performance measurement is very important, otherwise the analysis may lead to unrealistic scores, especially when its influence on costs is high, such as in the water utilities. In this paper, we study the influence of exogenous variables on the water utilities performance by applying conditional efficiency measures based on the order-m method and its probabilistic formulation. We use a sample of 66 water utilities operating between 2002 and 2008, representing about 70% of the Portuguese population. Our research suggests that inefficiency of Portuguese water utilities is substantial for some utilities: several exogenous variables might influence it considerably. For example, regulation has a positive influence on efficiency but when drinking water supply and wastewater services are provided by the same utility or when the wholesale and retail activities are provided together, the performance is lower. The effect of ownership is inconclusive and the variables residential customers, water source, peak factor, and density of customers have a mixed influence on performance which varies according to their scores.     

Ecological principles,biodiversity, and the electric utility industry

The synthetic field of conservation biology uses principles derived from many different disciplines to address biodiversity issues. Many of these principles have come from ecology, and two simple ones that seem to relate to many issues involving the utility industry are: (1) Everything is interconnected (and should usually stay that way), and (2) We can never do merely one thing. The first principle can be applied to both the biotic and physical environments that are impacted by industrial activities. Habitat fragmentation and the loss of physical and biotic connectedness that results are frequently associated with transmission rights-of-way. These problems can be reduced—or even turned into conservation benefits—by careful planning and creative management. The second principle applies to the utility industry's programs to deal with carbon released by burning fossil fuels. Ecological knowledge can allow these programs to contribute to the preservation of biodiversity in addition to addressing a pollution problem. Without careful ecological analyses, industry could easily create new problems while implementing solutions to old ones.     

小型都市工业园环境影响评价的研究——评价要点及技术方法的选择

分析了老工业基地城市小型都市工业园的具体情况;指出了对小型都市工业园进行环境影响评价的特殊目的;阐述了小型都市工业园进行环境影响评价应重视的要点;探索了小型都市工业园环境影响评价相应的技术方法。